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 ###Instrução: Qual Surface tem um Oponente na final de don mcneill e um Ano de 1940?
 ###Tabelas: CREATE TABLE mutya_ng_pilipinas_asia_pacific_titleholders_and_runners-up (mutya_ng_pilipinas_asia_pacific_titleholders_and_runners-up_id AUTO_INCREMENT PRIMARY KEY, Year INT, Mutya ng Pilipinas Asia Pacific VARCHAR, 1st runner-up VARCHAR, 2nd runner-up VARCHAR, 3rd runner-up VARCHAR, 4th runner-up VARCHAR) CREATE TABLE grand_slam (grand_slam_id AUTO_INCREMENT PRIMARY KEY, Outcome VARCHAR, Year INT, Championship VARCHAR, Surface VARCHAR, Opponent in the final VARCHAR, Score in the final VARCHAR) CREATE TABLE series_statistics (series_statistics_id AUTO_INCREMENT PRIMARY KEY, Game INT, Date VARCHAR, Location VARCHAR, Time VARCHAR, Attendance INT) CREATE TABLE doubles:_9_6_titles_–_3_runner-ups (doubles:_9_6_titles_–_3_runner-ups_id AUTO_INCREMENT PRIMARY KEY, Outcome VARCHAR, Date VARCHAR, Tournament VARCHAR, Surface VARCHAR, Partner VARCHAR, Opponents VARCHAR, Score VARCHAR) CREATE TABLE golden_globe_awards_–_fictional_presidents (golden_globe_awards_–_fictional_presidents_id AUTO_INCREMENT PRIMARY KEY, Year INT, Category VARCHAR, President VARCHAR, Nominee VARCHAR, Film or Television Series or Miniseries VARCHAR)  
SELECT Surface FROM grand_slam WHERE Opponent in the final = don mcneill AND Year = 1940